package com.wc.算法基础课.D第四讲数学知识.求组合数.求组合数_II;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

/**
 * @Author congge
 * @Date 2024/1/23 20:47
 * @description 求组合数 II
 * https://www.acwing.com/problem/content/description/888/
 */
public class Main {
    static FastReader sc = new FastReader();
    static PrintWriter out = new PrintWriter(System.out);
    static int n, a, b;
    static int N = 100010;
    static long[] fact = new long[N];
    static long[] infact = new long[N];
    static int P = (int) 1e9 + 7;

    // C(a,b) = a! / ((a - b)!b!)
    // 记得需要求逆元因为分母也modP
    public static void main(String[] args) {
        fact[0] = infact[0] = 1;
        for (int i = 1; i < N; i++) {
            fact[i] = fact[i - 1] * i % P;
            infact[i] = infact[i - 1] * qkm(i, P - 2, P) % P;
        }
        n = sc.nextInt();
        while (n-- > 0) {
            a = sc.nextInt();
            b = sc.nextInt();
            out.println(fact[a] * infact[a - b] % P * infact[b] % P);
        }
        out.flush();
    }

    static long qkm(long a, long b, long p) {
        long res = 1;
        while (b > 0) {
            if ((b & 1) == 1) res = res * a % p;
            a = a * a % p;
            b >>= 1;
        }
        return res;
    }
}

class FastReader {
    StringTokenizer st;
    BufferedReader br;

    FastReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    String nextLine() {
        String s = "";
        try {
            s = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return s;
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    // 是否由下一个
    boolean hasNext() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                String line = br.readLine();
                if (line == null)
                    return false;
                st = new StringTokenizer(line);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return true;
    }
}